Once more, a misogynist shocker gratuitously exploits the plight of womankind for the titillation of cinemagoers. Female emotional derangement is contrasted with masculine rationality. A woman is permitted short-lived sway over male oppression, only to be punished by having her naked body subjected to unspeakable indignity. I refer of course to The Proposal, which has mysteriously failed to attract the kind of fuss aroused by Lars von Trier's less insulting handling of the fairer sex's predicament.

Sandra Bullock's romcom turns the tables on the mainstream version of the format. Its forceful but unfeeling lead is female; her more demure but emotionally wiser foil is male. Not a very original variation, perhaps, but gosh, what a blow for feminism! As a ruthless boss, Bullock's character gets to make her male underlings work on the weekend of their gran's 90th, and to fire them whenever they happen to annoy her. She'll stop at nothing to advance her career. Just like a man!

Of course, this perversion of the "rightful" order of things cannot be allowed to persist. The uppity female must be taught to appreciate that any gal, however high-achieving, has to prioritise getting a guy. Fortunately for Bullock, she isn't required to snip off any of her private parts. Nonetheless, as the price of her regaining the box-office heights, she's still expected to tickle the lascivious by disrobing. Her dramatically ridiculous but much-hyped nude scene appears to have been devised simply to create advance buzz for the film, apparently successfully.

Meanwhile, elsewhere in the multiplex, Charlotte Gainsbourg's comeuppance may be more violent, but at least she manages to inflict on her manly murderer the time-honoured female counter-strokes of castration and hobbling. Both films nonetheless embody that enduring cinematic theme: the weirdness of women and the need to correct it, constrain it, quell it, laugh and ogle at it, or escape it.

The big screen presents us with an endless parade of bitches, witches, ditzes, hysterics, temptresses, flibbertigibbets, angels and goddesses – to be tortured, derided or worshipped as the case may be. The phenomenon is sometimes put down to the proclivities of male directors who have issues with the other gender. Von Trier, who thinks he's 65% female, may fit this bill. However, The Proposal's director is a woman, and one who seems reasonably normal. No, it seems more likely that our dream-weavers are simply trying to capitalise on age-old representations of womanhood.

The Proposal's notion of the dangerous shrew who must be tamed and domesticated can be traced back beyond Shakespeare into medieval Castilian literature. The threat posed by rampaging madwomen possibly infected by evil, like Gainsbourg's unfathomable harpy, has even deeper roots. Perhaps men fostered such ideas in the hope of buttressing the patriarchy. Perhaps they were also trying to explain to themselves their own susceptibility to feminine enchantment. Perhaps women sometimes connived at mystical representations of themselves to enhance their influence or to obtain the benefits of victimhood. Whatever. The world, surely, has now moved on.

We've grown out of the belief that over half of humanity aren't quite normal human beings. The blurring of gender roles has brought the era of female exceptionalism to a close. Women retain differences from men, but these no longer define them.

Cinema, however, seems wistfully reluctant to accept this. Perhaps it's even going backwards. The heroines of the black-and-white era were often more rounded and resourceful than their contemporary counterparts. In the 1929 version of The Taming of the Shrew, Mary Pickford is allowed to wink as she acknowledges a wife's duty to submit to her husband; Bullock is permitted no such ironic leeway as she knuckles under.

Women will doubtless remain queer cattle to some extent. Nonetheless, the movies could make do with fewer female freaks. It wouldn't hurt us to see some more women characters who are primarily people.